Power Source · Mon Sep 14
Gas Two-Stroke Mix for a Hedge Trimmer
Use the gas-to-oil ratio specified in your hedge trimmer’s manual or on its fuel label. Common ratios include 50:1 and 40:1, but they are not interchangeable unless the manufacturer says so.
The correct two-stroke fuel mix depends on your hedge trimmer’s engine. Check the owner’s manual, fuel-cap label, or manufacturer’s instructions for the required gasoline-to-oil ratio. Common ratios include 50:1 and 40:1, but do not assume either applies to your trimmer.
Make sure the tool is actually a two-stroke model. A four-stroke engine uses a different setup and should not run on premixed gas and oil unless its manual specifically instructs you to do so.
Measure the mix accurately
The ratio means parts of gasoline to one part of two-stroke oil, by volume. For one US gallon of gasoline, common examples are:
| Ratio |
Two-stroke oil per US gallon of gasoline |
| 50:1 |
About 2.6 US fluid ounces |
| 40:1 |
3.2 US fluid ounces |
| 32:1 |
4 US fluid ounces |
These are conversion examples, not recommendations for a particular trimmer. Follow the ratio in the manual, and use a measuring container marked for small fuel quantities. Don’t estimate by pouring.
Mix and handle fuel safely
Use fresh gasoline that meets the octane and ethanol limits in the manual, along with oil intended for air-cooled two-stroke engines and approved by the manufacturer. Do not substitute automotive motor oil. Use an approved fuel container, measure the oil and gasoline carefully, then close and gently shake the container to combine them. Label it as mixed fuel and keep it away from children, heat, and ignition sources.
Mix fuel outdoors or in a well-ventilated area, away from flames and sparks. Let a hot trimmer cool before refueling, and wipe up spills before starting it. Follow the manual’s fuel-storage guidance; old fuel can cause starting and running problems.
If the trimmer runs poorly after refueling
Stop the engine and check the fuel label and your measurements against the manual. If the ratio is wrong, or you are unsure what is in the tank, don’t keep running the trimmer. Let it cool and follow the manufacturer’s instructions for draining and disposing of fuel safely. Refill with fresh, correctly mixed fuel.
If it still runs poorly, check for a clogged air filter or spark arrestor and follow the manual’s maintenance steps. Persistent problems may need service. If the manual or label does not identify the fuel ratio, contact the manufacturer or an authorized service provider rather than guessing.
FAQ
Is 50:1 the right mix for every gas hedge trimmer?
No. Some trimmers specify 50:1, while others require a different ratio. Check the manual or fuel label for your exact model.
How much oil goes into one gallon of gas for a 50:1 mix?
A 50:1 ratio uses about 2.6 US fluid ounces of two-stroke oil per US gallon of gasoline. Use this only if your trimmer calls for 50:1.
Can I use regular motor oil in a two-stroke hedge trimmer?
No. Use two-stroke oil intended for the engine type and approved by the hedge trimmer’s manufacturer.
What should I do if I used the wrong fuel mix?
Stop running the trimmer. Check the manual for safe draining and refueling instructions, and use fresh fuel mixed to the specified ratio. Contact a service provider if the trimmer continues to run poorly.